Light emitting device with encapsulant formed with barriers and light emitting device package having the same

ABSTRACT

Provided are a light emitting device, a light emitting device package, and a lighting system. The light emitting device (LED) comprises an LED chip, a barrier over the LED chip, and an encapsulating material containing a phosphor, wherein the encapsulating material is disposed inside the barrier over the LED chip.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a 37 C.F.R. §1.53(b) continuation of U.S.patent application Ser. No. 12/909,438 filed Oct. 21, 2010, which claimspriority on Korean Patent Application No. 10-2009-0100654, filed Oct.22, 2009, the entire contents of all which are hereby incorporated byreference and for which priority is claimed under 35 U.S.C. §120.

BACKGROUND

Embodiments relate to a light emitting device, a light emitting devicepackage, and a lighting system.

A light emitting device (LED) may be implemented by combining a p-njunction diode, which has a characteristic converting an electricalenergy to a light energy, with Group III and V elements of a PeriodicTable. The LED may implement various colors by adjusting a compositionratio of a compound semiconductor.

Three LEDs (i.e., red LED, green LED, and blue LED) that respectivelyemit light having red, green, and blue colors (three primary colors) maybe combined with each other, a yellow phosphor (using phosphors such asyttrium aluminum garnet (YAG) and terbium aluminum garnet (TAG)) may beadded to the blue LED, or three-colored (red/green/blue) phosphors maybe applied to an UV LED to realize a white LED package.

However, in a related art white LED package using a phosphor, thephosphor within an encapsulating material may be precipitated on abottom of the LED package as time passed after molding. Thus, there is alimitation that the phosphor is non-uniformly distributed around the LEDchip to wide a distribution of a color temperature.

Also, according to a related art, the phosphor may have a distributionarea relatively greater than an area of an LED. Thus, there is alimitation that the phosphor is non-uniformly distributed around the LEDto wide the distribution of the color temperature.

SUMMARY

Embodiments provide a light emitting device in which a phosphor isuniformly distributed therearound, a light emitting device package, anda lighting system.

In one embodiment, a light emitting device (LED) comprises: an LED chip;a barrier over the LED chip; and an encapsulating material containing aphosphor, wherein the encapsulating material is disposed inside thebarrier over the LED chip.

In another embodiment, an LED package comprises: a submount; an LED chipover the submount; a barrier over the LED chip; and an encapsulatingmaterial containing a phosphor, wherein the encapsulating material isdisposed inside the barrier over the LED chip.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features will be apparent fromthe description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a light emitting device (LED) packageaccording to a first embodiment.

FIG. 2 is a plan view of the LED package according to the firstembodiment.

FIGS. 3 to 6A are sectional views for explaining a method ofmanufacturing the LED package according to the first embodiment.

FIGS. 6B and 6C are other sectional views of the LED package accordingto the first embodiment.

FIG. 6D is a sectional view of an LED according to an embodiment.

FIG. 7 is a plan view of an LED package according to a secondembodiment.

FIG. 8 is a plan view of an LED package according to a third embodiment.

FIG. 9 is a sectional view of an LED package according to a fourthembodiment.

FIG. 10 is a perspective view of a lighting unit according to anembodiment.

FIG. 11 is an exploded perspective view of a backlight unit according toan embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, a light emitting device (LED), an LED package, and alighting system will be described in detail with reference to theaccompanying drawings.

In the description of embodiments, it will be understood that when alayer (or film) is referred to as being ‘on’ another layer or substrate,it can be directly on another layer or substrate, or intervening layersmay also be present. Further, it will be understood that when a layer isreferred to as being ‘under’ another layer, it can be directly underanother layer, and one or more intervening layers may also be present.In addition, it will also be understood that when a layer is referred toas being ‘between’ two layers, it can be the only layer between the twolayers, or one or more intervening layers may also be present.

Embodiment

FIG. 1 is a sectional view of a light emitting device (LED) packageaccording to a first embodiment, and FIG. 2 is a plan view of the LEDpackage according to the first embodiment. FIG. 1 is a sectional viewtaken along line I-I′ of FIG. 2.

An LED package 500 according to an embodiment may include a submount100, an LED chip 200 disposed on the submount 100, a barrier 310disposed on the LED chip 200, and an encapsulating material 400containing a phosphor on the LED chip 200.

The barrier 310 may be disposed on an outer top surface of the LED chip200. For example, the barrier 310 may include a barrier connected to anouter circumference of the LED chip 200, but is not limited thereto.

The encapsulating material 400 may have a flat top surface, but is notlimited thereto. When the encapsulating material 400 has the flat topsurface, an optical design may be easy through surface emission.

Since the encapsulating material 400 has the flat top surface and aroughness (not shown) is disposed on an upper surface of theencapsulating material 400, external light extraction efficiency may beimproved.

According to the LED and LED package of the embodiment, the barrier 310may be disposed around the LED to uniformly distribute the phosphoraround the LED. Thus, the density of the phosphor may be increased tonarrow a distribution of a color temperature of the LED.

Hereinafter, a method of manufacturing the LED package according to thefirst embodiment will be described with reference to FIGS. 3 to 6A.Although the LED package is mainly described below, the embodiment isnot limited thereto. As shown FIG. 6D, a barrier and a phosphor layermay be formed on the LED chip in a chip level.

First, as shown in FIG. 3, the submount 100 is prepared.

The submount 100 has a thermal expansion coefficient similar to that ofa material of the LED chip. Also, the submount 100 may be formed of amaterial having superior thermal conductivity. For example, according tothe present embodiment, the submount 100 may be formed of a siliconmaterial, a synthetic resin material, or a metallic material, but is notlimited thereto.

Also, the submount 100 may include a reflector cup (not shown). Inaddition, a device having a Zener diode shape may be disposed in thesubmount 100 to prevent an electro static discharge from occurring.

Next, an LED chip 200 is attached to the submount 100.

The LED chip 200 may be formed of GaN, GaAs, GaAsP, or GaP. For example,green-blue LEDs may be formed of GaN(InGaN) and yellow-red LEDs may beformed of InGaAIP, or AIGaAs, but are not limited thereto.

The LED chip 200 illustrated in FIG. 4 may be a vertical type LED chip,but is not limited thereto.

Referring to FIG. 4, the LED chip 200 may include a light emittingstructure 210 formed on a second electrode 220. The second electrodelayer 200 may include at least one of an ohmic layer, a reflectionlayer, a junction layer, and a conductive supporting substrate. Thelight emitting structure 210 may include a second conductive typesemiconductor layer 212, an active layer 214, and a first conductivetype semiconductor layer 216.

The first conductive type semiconductor layer 212 may be formed of aIII-V compound semiconductor in which a first conductive type dopant isdoped. In case where the first conductive type semiconductor layer 212is an N-type semiconductor layer, the first conductive type dopant mayinclude Si, Ge, Sn, Se, or Te as the N-type dopant, but is not limitedthereto.

The first conductive type semiconductor layer 212 may be formed of asemiconductor material having a compositional formula ofIn_(x)Al_(y)Ga_(1-x-y)N (0≦x≦1, 0≦y≦1, 0≦x+y≦1).

The first conductive type semiconductor layer 212 may be formed of atleast one of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs,InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP.

The active layer 214 may have at least one of a single quantum wellstructure, a multi quantum well (MQW) structure, a quantum-wirestructure, and a quantum dot structure. For example, the active layer214 may have the MQW structure formed by injecting trimethyl gallium(TMGa) gas, ammonia (NH₃) gas, nitrogen (N₂) gas, and trimethyl indium(TMIn) gas, but is not limited thereto.

A well layer/barrier layer of the active layer 214 may be have at leastone pair structure of InGaN/GaN, InGaN/InGaN, AlGaN/GaN, InAlGaN/GaN,GaAs(InGaAs)/AlGaAs, GaP(InGaP)/AlGaP, but is not limited thereto. Thewell layer may be formed of a material having a band gap lower than thatof the barrier layer.

A conductive clad layer may be formed over or/and below the active layer214. The conductive clad layer may be formed of an AlGaN-basedsemiconductor and may have a band gap higher than that of the activelayer 214.

The second conductive type semiconductor layer 216 may be formed of aIII-V compound semiconductor in which a second conductive type dopant isdoped, for example, a semiconductor material having a compositionalformula of In_(x)Al_(y)Ga_(1-x-y)N (0≦x≦1, 0≦y≦1, 0≦x+1). The secondconductive type semiconductor layer 216 may be formed of at least one ofGaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP,and AlGaInP. In case where the second conductive type semiconductorlayer 216 is a P-type semiconductor layer, the second conductive typedopant may include Mg, Zn, Ca, Sr, Ba, or the like as a P-type dopant.The second conductive type semiconductor layer 216 may be formed in asingle- or multi-layer structure, but is not limited thereto.

In the present embodiment, the first conductive type semiconductor layer212 may be implemented by an N-type semiconductor layer and the secondconductive type semiconductor layer 116 may be implemented by a P-typesemiconductor layer and vice versa. Also, a semiconductor layer having apolarity opposite to that of the second conductive type, e.g., an N-typesemiconductor layer (not shown) may be formed over the secondsemiconductor layer 216. As a result, the light emitting structure 210may have at least one of an N-P junction structure, a P-N junctionstructure, an N-P-N junction structure, and a PN-P junction structure.

For example, the second electrode layer 220 may include the ohmic layer(not shown), and the ohmic layer may ohmic-contact the light emittingstructure 210 to smoothly supply a power to the light emitting structure210. Also, the ohmic layer may be formed by multi-stacking a singlemetal layer or a metal alloy layer and a metal oxide layer.

For example, the ohmic layer may be formed of at least one of indium tinoxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO),indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO),indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tinoxide (ATO), gallium zinc oxide (GZO), IZO Nitride (IZON), Al—Ga ZnO(AGZO), In—Ga ZnO (IGZO), ZnO, IrOx, RuOx, NiO, RuOx/ITO, Ni/IrOx/Au,Ni/IrOx/Au/ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, andHf, but is not limited thereto.

Also, the second electrode layer 220 may include the reflection layer(not shown) to reflect light incident from the light emitting structure210, thereby improving light extraction efficiency.

For example, the reflection layer may be formed of a metal or alloyincluding at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au,and Hf. Also, the reflection layer may be formed in a multi-layerstructure using the foregoing metal or alloy and a transparentconductive material such as IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, etc.,for example, may be stacked with IZO/Ni, AZO/Ag, IZO/Ag/Ni, AZO/Ag/Ni,or the like.

Also, in case where the second electrode layer 220 may include thejunction layer, the reflection layer may function as the junction layer,or may include a barrier metal or bonding metal. For example, thejunction layer may be formed of at least one of Ti, Au, Sn, Ni, Cr, Ga,In, Bi, Cu, Ag, and Ta.

Also, the second electrode layer 120 may include the conductivesupporting substrate. The conductive supporting substrate may supportthe light emitting structure 210 and supply a power to the lightemitting structure 210. The conductive supporting substrate may beformed of a metal, a metal alloy or a conductive semiconductor materialthat have superior conductivity.

For example, the conductive supporting substrate may be formed of atleast one of copper (Cu), Cu alloy, gold (Au), nickel (Ni), molybdenum(Mo), Cu—W, a carrier wafer (e.g., Si, Ge, GaAs, GaN, ZnO, SiGe, SiC,Ga₂O₃, etc.).

Next, the LED chip 200 may be attached to the submount 100 through aflip chip method, a method in which the LED chip is attached using apolymer adhesive, or a plated eutectic metal.

For example, the LED chip may be attached through a soldering processusing an Ag conductive epoxy having superior processability or aeutectic bonding process in case where highly thermal conductivity isrequired, but is not limited thereto.

Referring to FIG. 5, a barrier material 310 a is formed on the LED chip200. The barrier material 310 a may be formed of a non-conductivematerial or a conductive material. For example, the non-conductivematerial may include a photoresist (PR) material, an oxide layer, and anitride layer, but is not limited thereto.

In case where the barrier material 310 a is formed of the conductivematerial, the barrier may be configured to prevent the LED chip frombeing short-circuited.

Referring to FIG. 6A, a portion of the barrier material 310 a is removedto form a barrier 310 on an outer top surface of the LED chip 200. Forexample, when the barrier material 310 a is a photoresist layer,exposure and developing processes may be performed to form the barrier310. Also, when the barrier material 310 a is formed of an insulatingmaterial, an etch process may be performed to form the barrier 310.

In the present embodiment, the barrier 310 may be formed using athixotropic material without performing the removal process. Forexample, the barrier 310 may be formed on the outer top surface of theLED chip 200 using Ag epoxy having thixotropy by which the epoxy doesnot run down to maintain its form.

The barrier 310 may be connected to an outer circumference of the LEDchip, but is not limited thereto.

According to the LED and the LED package, the barrier may be formedaround the LED, and then an encapsulating material containing a phosphormay be encapsulated adjacent to the LED chip in a next process. Thus,the phosphor may be uniformly distributed around the LED chip.

Alternatively, a wire junction process except for the flip chip processmay be performed to allow current to flow into the LED chip. Forexample, the wire junction process may be performed once in case of thevertical type LED chip. Also, in case of a lateral type LED chip, thewire junction process may be performed two times. The wire may includeat least one of an Ag wire, a copper wire, and an aluminum wire. Thewire junction process may be performed through a ball wire junctionprocess or an edge wire junction process.

Next, the encapsulating material 400 containing the phosphor (not shown)is encapsulated on the LED chip 200 to protect the chip and improvelight extraction efficiency.

The encapsulating material 400 may include an epoxy encapsulatingmaterial or a silicon encapsulating material, but is not limitedthereto.

In the present embodiment, the LED chip may be an LED, which emitsvisible light such as green-blue or yellow-red LEDs or an UV LED. Here,the phosphor may be added to the encapsulating material 400 emit whitelight.

For example, in the present embodiment, a yellow phosphor (using aphosphor such as YAG or TAG) may be added to a blue LED to emit thewhite light. Alternatively, three-colored (red/green/blue) phosphors maybe applied to an UV LED to emit the white light. However, the presentdisclosure is not limited thereto.

The phosphor may contain a host material and an active material. Forexample, a cerium active material may be applied to a host material suchas yttrium aluminum garnet (YAG), or a europium (Eu) active material maybe applied to a silicate-based host material, but is not limitedthereto.

The encapsulating process may be performed in order of a combiningprocess, a mixing process, a discharging process, and a curing process.A method of encapsulating the encapsulating material 400 may include adispensing method, a casting molding method, a transfer molding method,and a vacuum printing method.

The encapsulating material 400 may have a flat top surface, but is notlimited thereto. Since the encapsulating material 400 is uniformlyformed on the LED chip 200 in a flat shape, the phosphor may beuniformly distributed around the LED chip 200, and also an opticaldesign may be easy through surface emission.

In the present embodiment, a roughness (not shown) may be formed on atop surface of the encapsulating material 400 to improve the lightextraction efficiency. For example, a wet etching process may bepartially performed after the encapsulating process is performed topartially form the roughness on the top surface of the encapsulatingmaterial 400. Alternatively, the transfer molding process may beperformed using a mold on which a roughness is formed to form theroughness on the top surface of the encapsulating material 400.

Thereafter, an external lens (not shown) having a hemisphere shape maybe formed on the encapsulating material 400 to improve the lightextraction efficiency and protect the wire (not shown).

According to the LED and the LED package of the present embodiment, thebarrier may be formed around the LED to encapsulate the encapsulatingmaterial 400 containing the phosphor in a position adjacent to the LEDchip. Therefore, the phosphor may be uniformly distributed around theLED chip.

According to the present embodiment, the barrier 310 may be formed alongan outer circumference of an electrode pad (not shown) to prevent theencapsulating material 400 containing the phosphor from being formed onthe electrode pad of the LED chip 200. Also, the barrier 310 may coverthe outer circumference of the LED chip 200 and the electrode pad toform the encapsulating material 400 containing the phosphor. Then, onlythe barrier 310 formed on the electrode pad may be removed, or theentire battier 310 may be removed.

FIGS. 6B and 6C are other sectional views of the LED package accordingto the first embodiment.

As shown in FIG. 6B, a barrier 312 is disposed on a lateral surface ofan LED chip 200 to serve as a passivation function.

Also, as shown in FIG. 6C, the process shown in FIG. 6A may be performedto remove the barrier 310.

FIG. 6D is a sectional view of an LED according to an embodiment.

The present embodiment is not limited to the LED package. For example,as shown in FIG. 6D, a barrier 310 is disposed on an LED chip 200, andan encapsulating material 400 containing a phosphor may be disposed.Thereafter, a packaging process may be performed using the LED chip 200including the encapsulating material 400 and the barrier 310.

FIG. 7 is a plan view of an LED package according to a secondembodiment. A sectional view taken along line of FIG. 7 may be similarto that of FIG. 1.

The second embodiment may adopt technical characteristics of the firstembodiment. Thus, characteristics of the second embodiment will bemainly described below.

In the second embodiment, barriers 320 may be disposed on an outercircumference of the LED chip in a state where they 320 are separatedfrom each other. For example, the barrier 320 according to the secondembodiment may include first to fourth barriers 321, 322, 323, and 324,which are separated from each other, but is not limited thereto.According to the second embodiment, since the barriers 320 separatedfrom each other are disposed on the outer circumference of the LED chip200, a light-shielding area may be minimized and an encapsulatingmaterial containing a phosphor may be encapsulated adjacent to the LEDchip 200. Thus, the phosphor may be uniformly distributed around the LEDchip 200.

FIG. 8 is a plan view of an LED package 500 c according to a thirdembodiment. A sectional view taken along line III-III′ of FIG. 8 may besimilar to that of FIG. 1.

The third embodiment may adopt technical characteristics of the firstand second embodiments. Thus, characteristics of the third embodimentwill be mainly described below.

Barriers 330 according to the third embodiment may be disposed on anouter circumference of an LED chip 200 in a state where they 330 areseparated from each other. For example, the barriers 330 according tothe third embodiment may include first to fourth barriers 331, 332, 333,and 334, which are separated from each other, but is not limitedthereto.

In the third embodiment, at least one of the first to fourth barriers331, 332, 333, and 334, which are separated from each other, may be apad. For example, the fourth barrier 334 may be the pad, but is notlimited thereto. Here, the pad for the barrier may be formed in a LEDchip process.

At least one of the first to fourth barriers 331, 332, 333, and 334,which are separated from each other, may be an actual pad, and the restbarriers may be dummy pads.

According to the third embodiment, since the barriers separated fromeach other are disposed on the outer circumference of the LED chip 200using the pad, a light-shielding area may be minimized and anencapsulating material containing a phosphor may be encapsulatedadjacent to the LED chip to uniformly distribute the phosphor around theLED chip.

FIG. 9 is a sectional view of an LED package 500 d according to a fourthembodiment.

The fourth embodiment may adopt technical characteristics of the firstto third embodiments. Thus, characteristics of the fourth embodimentwill be mainly described below.

In the fourth embodiment, an encapsulating material 420 may have ahemisphere shape. The encapsulating material 420 may be maintained in auniform shape by a surface tension thereof to uniformly distribute aphosphor.

As a result, according to the present embodiment, since theencapsulating material is maintained on an LED chip 200 in the uniformshape by the surface tension thereof, the phosphor may be uniformlydistributed in the encapsulating material. As a result, the distributionof the phosphor is uniform, and furthermore, the phosphor may beuniformly distributed with an area similar to that of the LED chip.

According to the present embodiment, a surface of the LED chip may havewettability to uniformly form the encapsulating material 420 on the LEDchip 200 by the surface tension thereof.

For example, when a roughness (not shown) is disposed on a surface ofthe LED chip 200, the wettability of the encapsulating material 420 maybe reduced to form the encapsulating material 420 having a hemisphereshape. Furthermore, light extraction efficiency may be improved.

According to the fourth embodiment, the encapsulating material 420 mayhave the hemisphere shape to improve the light extraction efficiency.Also, since a barrier 310 is disposed on an outer circumference of theLED chip 200, the encapsulating material 420 containing a phosphor maybe distributed adjacent to the LED chip 200. Therefore, the phosphor maybe uniformly distributed around the LED chip 200.

A plurality of LED packages 500 according to the embodiments may bearrayed on a substrate. Optical members such as a light guide plate, aprism sheet, a diffusion sheet, and a fluorescence sheet may be disposedon a path of light emitted from the LED package 500. The LED package500, the substrate and the optical members may function as a backlightunit or lighting unit. For example, the lighting system may include abacklight unit, a lighting unit, an indicator unit, a lamp, astreetlamp, etc.

FIG. 10 is a perspective view of a lighting unit 1100 according to anembodiment. The lighting unit 110 shown in FIG. 10 is an example of thelighting system, but is not limited thereto.

Referring to FIG. 10, the lighting unit 1100 may include a case body1110, a light emitting module part 1130 installed in the case body 1110,and a connection terminal 1120 installed in the case body 1110 andreceiving an electric power from an external power supply.

The case body 1110 may be formed of a material having a good heatdissipation characteristic, for example, a metal material or a resinmaterial.

The light emitting module part 1130 may include a substrate 1132 and atleast one an LED package 500 mounted on the substrate 1132.

The substrate 1132 may be a substrate in which circuit patterns areprinted on an insulator. For example, the substrate 1132 may include ageneral printed circuit board (PCB), a metal core PCB, a flexible PCB, aceramic PCB, etc.

Also, the substrate 1132 may be formed of a material capable ofefficiently reflecting light or may have a surface having a colorcapable of efficiently reflecting light, for example, a white color, ora silver color.

The at least one LED package 500 may be mounted on the substrate 1132.Each of the LED packages 500 may include at least one light emittingdevice (LED) chip 200. The LED chip 200 may include colored lightemitting diodes that respectively emit colored light such as red, green,blue or white light and a UV light emitting diode that emits ultravioletrays.

The light emitting module part 1130 may have a combination of variousLED packages 200 to obtain desired color tone and luminance. Forexample, the light emitting module part 1130 may have a combination of awhite LED, a red LED, and a green LED to obtain a high color renderingindex (CRI).

The connection terminal 1120 may be electrically connected to the lightemitting module part 1130 to supply a power. As shown in FIG. 10, theconnection terminal 1120 may be screwed and coupled to an external powersource in a socket type, but is not limited thereto. For example, theconnection terminal 1120 may be manufactured in a pin shape, and thusthe connection terminal 1120 may be inserted into the external powersource or connected to the external power source through a wire.

FIG. 11 is an exploded perspective view of a backlight unit 1200according to an embodiment. The backlight unit 1200 shown in FIG. 11 isan example of lighting systems, and is not limited thereto.

The backlight unit 1200 according to the embodiment may include a lightguide plate 1210, a light emitting module part 1240 supplying light tothe light guide plate 1210, a reflective member 1220 below the lightguide plate 1210, and a bottom cover 1230 receiving the light guideplate 1210, the light emitting module part 1240, and the reflectivemember 1220, but is not limited thereto.

The light guide plate 1210 diffuses light to produce planar light. Thelight guide plate 1210 may be formed of a transparent material. Forexample, the light guide plate 1210 may be formed of one of an acrylicresin-based material such as polymethylmethacrylate (PMMA), apolyethylene terephthalate (PET) resin, a poly carbonate (PC) resin, acyclic olefin copolymer (COC) resin, and a polyethylene naphthalate(PEN) resin.

The light emitting module part 1240 provides light to at least one sidesurface of the light guide plate 1210, and finally acts as a lightsource of a display device in which the backlight unit is installed.

The light emitting module part 1240 may contact the light guide plate1210, but is not limited thereto. Particularly, the light emittingmodule part 1240 may include a substrate 1242 and a plurality of LEDpackages 500 mounted on the substrate 1242. The substrate 1242 maycontact the light guide plate 1210, but is not limited thereto.

The substrate 1242 may be a PCB including circuit patterns (not shown).The substrate 1242 may include a metal core PCB (MCPCB), a flexible PCB(FPCB), etc. as well as the general PCB, but is not limited thereto.

The plurality of LED packages 200 may be mounted on the substrate 1242so that light emitting surfaces of the LED packages 200 are spaced apredetermined distance from the light guide plate 1210.

The reflective member 1220 may be disposed below the light guide plate1210. The reflective member 1220 reflects light incident from a bottomsurface of the light guide plate 1210 to allow the reflected light to bedirected toward an upper direction, thereby improving brightness of thebacklight unit. The reflective member 1220 may be formed of, forexample, PET, PC, PVC resin, or the like, but is not limited thereto.

The bottom cover 1230 may receive the light guide plate 1210, the lightemitting module part 1240, and the reflective member 1220. For thispurpose, the bottom cover 1230 may be formed in a box shape with a topsurface opened, but is not limited thereto.

The bottom cover 1230 may be formed of a metal material or a resinmaterial. In addition, the bottom cover 1230 may be manufactured byusing a process such as a press molding or an injection molding.

As described above, the lighting system according to the embodiments mayinclude the LED package according to the embodiments to improve thereliability of the LED.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A light emitting device comprising: a lightemitting diode chip; a barrier on a top surface of the light emittingdiode chip; and an encapsulant including a phosphor at an inner portionof the barrier on the light emitting diode chip, wherein a lateral widthof the light emitting diode chip is substantially the same with alateral width of the encapsulant including the phosphor.
 2. The lightemitting device as claimed in claim 1, wherein the barrier includes athixotropic material.
 3. The light emitting device as claimed in claim1, wherein the barrier includes at least two barriers separated fromeach other at an outer peripheral portion of the light emitting diodechip.
 4. The light emitting device as claimed in claim 3, wherein one ofthe barriers is a dummy pad, and the other one of the barriers is a pad,and wherein the dummy pad is not electrically connected to the pad. 5.The light emitting device as claimed in claim 1, wherein the barriercomprises a plurality of barriers separated from each other, and thebarriers are disposed on a substantially center portion of the outerperipheral portion of the light emitting diode chip.
 6. The lightemitting device as claimed in claim 1, wherein the barrier is formed onboth a side surface and a top surface of an outer peripheral portion ofthe light emitting diode chip.
 7. The light emitting device as claimedin claim 1, wherein the barrier comprises four barriers separated fromeach other at an outer peripheral portion of the light emitting diodechip.
 8. The light emitting device as claimed in claim 7, wherein atleast one of the barriers comprises a dummy pad, and at least one of thebarriers comprises a pad, and wherein the dummy pad is not electricallyconnected to the pad.
 9. The light emitting device as claimed in claim1, wherein the barrier is formed on a top surface of an outer peripheralportion of the light emitting diode chip.
 10. The light emitting deviceas claimed in claim 1, wherein the barrier is connected to an outerperipheral portion of the light emitting diode chip.
 11. The lightemitting device as claimed in claim 1, wherein the barrier includes aconductive material or a nonconductive material.
 12. The light emittingdevice as claimed in claim 1, wherein the encapsulant has a flat topsurface.
 13. The light emitting device as claimed in claim 12, whereinthe flat top surface is substantially the same as a flat top of thebarrier.
 14. The light emitting device as claimed in claim 1, whereinthe encapsulant has a hemispherical shape.
 15. The light emitting deviceas claimed in claim 1, wherein the encapsulating material comprises aflat top surface and the flat top surface of the encapsulating materialcomprises a roughness.
 16. A light emitting device comprising: a lightemitting diode chip; a barrier on the light emitting diode chip; and anencapsulant including a phosphor at an inner portion of the barrier onthe light emitting diode chip, wherein the encapsulating materialcomprises a flat top surface and wherein the flat top surface issubstantially the same as a flat top of the barrier.
 17. The lightemitting device as claimed in claim 16, wherein the barrier includes atleast two barriers separated from each other at an outer peripheralportion of the light emitting diode chip, and wherein one of thebarriers is a dummy pad, and the other one of the barriers is a pad, andwherein the dummy pad is not electrically connected to the pad.
 18. Thelight emitting device as claimed in claim 16, wherein the barriercomprises four barriers separated from each other at an outer peripheralportion of the light emitting diode chip, and wherein at least one ofthe barriers comprises a dummy pad, and at least one of the barrierscomprises a pad, and wherein the dummy pad is not electrically connectedto the pad.
 19. The light emitting device as claimed in claim 16,wherein the barrier comprises at least two barriers separated from eachother, and the barriers are disposed on a substantially center portionof the outer peripheral portion of the light emitting diode chip. 20.The light emitting device as claimed in claim 16, wherein the barrier isformed on both a side surface and a top surface of an outer peripheralportion of the light emitting diode chip.